How to put anti wind up (integrator clamping) for PI in simulink

I am using saturation block, but that creates error.

Answer 1

[Birdman]

You don't have to create anything on your own. Go to PID Controller block in Simulink, double click it, open PID Advanced part of it. Check Limit output part and then the Anti-windup method will become visible. Then, you can choose clamping as a method. Hope this helps.

[Ramu Nair R]

Thanks for your answer. But i would like to make one myself.

[Birdman]

That is also possible. Again, go to PID Controller and set its anti-windup method as Clamping as I said before. Click Apply and close the Block Parameters pane. Then, right click PID Controller and select Mask->Look Under Mask. You will encounter a block diagram as attached in figure. You can make one for yourself.

Answer 2

[John Harris]

The PID controller uses the Saturation block. If you don't want a Saturation block, or if your max and min are dynamic, you need to roll your own. The logic is something like,

if(in>max);     out=max;
elseif(in<min); out=min;
else;           out=in;
end

This logic could be put in a subsystem using any of the following:

 * relative operators & Switches
 * relative operators, Enabled Subsystems, Merge
 * if block, If-Action subsystems, Merge,

and then your subsystem could be a block in your custom library...you could find it useful again.

Answer 3

[sanjeev]

Hi,

Please find PID with Anti Wind-up from Astrom book.

K: proportional gain,

K/Ti: integral gain,

KTd: derivative gain,

Tt = sqrt(Ti*Td)

Actuator model = Saturation block (you can define upper and lower depends on hardware you are using)

es = control implemented - control generated